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An Epistemology Update

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1 An Epistemology Update
John Rafferty MA MSc PGCE Senior Lecturer Social Sciences Langside College Glasgow Tel:

2 Philosophical Issues in Epistemology
Section 1 Philosophical Issues in Epistemology

3 Outcome 1 Demonstrate an understanding of the philosophical issues in the area of epistemology: The Tripartite Theory of Knowledge Philosophical Problems with the Tripartite theory Scepticism, Rationalism and Empiricism

4 Why are knowledge claims a problem in philosophy?
Question 1 Why are knowledge claims a problem in philosophy?

5 Appearance and Reality
Perceptual problems Colour blindness; hallucinations Optical illusions The stick in water isn’t bent Atmospheric effects Mirages as they appear; Stars don’t twinkle Time lapse illusions Some stars no longer exist Radical philosophical doubt Descartes’ Demon; Plato’s Cave; The Matrix; Brain in a Jar

6 Illusions of perspective

7 Light refraction

8 Objects on the horizon

9 Railway tracks

10 Belief, Knowledge & Certainty
A proposition that is held to be true but without sufficient evidence to convince others Knowledge A proposition that is believed, is true and can be supported by evidence Certainty A proposition where there is no doubt about its truth

11 Question 2 What is knowledge?

12 ‘Knowing how’ v ‘knowing that’
A distinction associated with Gilbert Ryle ( ) Knowing that Facts and information; propositional knowledge; “I know that Berlin is in Germany” Knowing how An ability or skill; a dispositional or operational knowledge; “I know how to bake bread” Most of epistemology has been concerned with knowing that, especially classical debates Can all cases of ‘knowing how’ be reduced to collections of ‘knowing that’? E.g. Knowing how to drive a car Is knowing that useless without knowing how? Is innatism only tenable as applied to knowing how?

13 The Tripartite Theory of knowledge
A classical definition of knowledge An agent (A) can be said to know a proposition (P) if: P is true (the truth condition) A believes P (the belief condition) A has sufficient evidence for P (the evidence condition This definition of knowledge is called “Justified true belief” Having two of these conditions is not enough to count as knowledge.

14 The Hesitant Student Teacher: Billy, what is 3x7?
Billy: Er…(guesses) is it 21? In this case p is true (3x7 is 21) and Billy has evidence for p (he has been to the classes) but he doesn’t believe P. Is this a case of knowledge?

15 The Lucky Punter A gambler finds a four leaf clover so bets on a horse that day believing that his horse will win now that he has this lucky charm. The horse does win. In this case p is true (the horse did win) and the punter believed p (he sincerely thought the horse would win) but his evidence for this belief seems inadequate. Is this a case of knowledge?

16 Santa’s Visit Many children believe in Santa Claus. They leave cookies out for him that are eaten the next morning and as promised the presents arrive every Christmas day. Parents, shopkeepers and teachers all reinforce this belief. In this case the children believe P (they think Santa is real) and have evidence for believing P (teachers and parents confirm it) but P isn’t true Is this knowledge?

17 Problems with the tripartite theory
The Gettier Problem Smith has applied for a job, but has a justified belief that "Jones will get the job". He also knows that "Jones has 10 coins in his pocket". Smith therefore concludes that "the man who will get the job has 10 coins in his pocket". In fact, Smith gets the job but, as it happens, also has 10 coins in his pocket. So his belief that "the man who will get the job has 10 coins in his pocket" was justified and true but isn’t knowledge. Infinite regress argument Every justification in turn requires justification and arguably this demand for justification is never sated. Some justifications are unreliable Sense experience is prone to deception Innate ideas are controversial Analytic truths are trivially true

18 Can knowledge claims be justified?
Question 3 Can knowledge claims be justified?

19 Rationalism and Empiricism
Reason is the source of all knowledge Mind contains innate ideas Maths is a model for knowledge Knowledge can be gained a priori Knowledge can be certain The senses are easily fooled Examples: Plato, Augustine; Descartes; Leibniz Empiricism The senses are the source of all knowledge Mind is a ‘tabula rasa’ Biology is a model for knowledge Knowledge is only gained a posteriori Knowledge can only ever be probable Reason only gives us access to uninformative tautologies Examples: Aristotle (?) Locke; Berkeley; Hume

20 Classic Texts in Epistemology
Section 2 Classic Texts in Epistemology

21 Outcomes 2 & 3 Critically analyse a standard philosophical position in the area of epistemology: Describe the epistemology of Descartes or Hume Explain the reasoning and assumptions on which this account is based Cite specific extracts Critically evaluate a standard philosophical position in the area of epistemology: Explain the strengths and weaknesses of Descartes or Hume Present a conclusion on the persuasiveness of this account Give reasons in support of this conclusion

22 Section 2: Option 1 René Descartes

23 Meditations on First Philosophy
René Descartes Meditations on First Philosophy

24 Historical Context The Renaissance The end of Scholasticism
Rebirth in knowledge Flourishing in the arts Architecture Painting Science

25 Historical Context The Reformation Split in the church
Birth of Protestantism Catholic dominance ends Europe divided Martin Luther

26 Historical Context Discovery of the New World New cultures and peoples
New world view

27 Meditation 1 The Sceptical Method
René Descartes Meditation 1 The Sceptical Method

28 Method Assume nothing Start afresh Re-examine his beliefs
Focus on foundational beliefs Reject obvious falsehoods But also reject even slightly doubtful beliefs Looking for 1 certainty to base his knowledge on Architectural metaphor Barrel of apples analogy

29 Attacking Sense Experience
Objects in the distance Small objects Other arguments from illusion are possible But surely apart from these the senses are reliable?

30 Dreaming Argument A stronger argument against sense experience
Any given sense experience can be replicated in dreams Hence sense experience is unreliable In fact, there is never any sure way of distinguishing dreams from reality

31 A Priori truths Dreams are like paintings
They must be based on reality Or at least the colours and shapes must be real Whether awake or asleep a square still has 4 sides Hence maths and geometry escape the dream argument and may be reliable

32 Do all dreams contain some knowledge?

33 The Demon Hypothesis An argument against a priori knowledge
The ultimate in scepticism A test which any candidate for certainty must pass Imagine a demon were fooling us in everything we see and think If this scenario were true, could anything still be certain? This idea has reappeared in different forms

34 Meditation 2 Finding Certainty
René Descartes Meditation 2 Finding Certainty

35 The Search for Certainty
Restates his sceptical approach Like Archimedes he is looking for 1 fixed point Assumes he has no body Assumes everything revealed by the senses is a lie Assumes the Demon fools him at every turn Can anything be known if we assume all this?

36 The Cogito Cogito ergo sum Defeats the Dreaming Argument
I am, I exist (Meditations) I think therefore I am (Discourse) Defeats the Dreaming Argument you must exist to dream Defeats the Demon Hypothesis You must exist to be fooled A self-authenticating statement You affirm its truth each time you think it But surely we know external objects better than we know the mind?

37 Rationalism and Empiricism
A major dispute running through the entire history of philosophy has to do with the source(s) of human knowledge. There are two major schools: rationalism and empiricism. The empiricists hold that knowledge is derived from sense perception and experience. The rationalists (such as Descartes) hold that knowledge is derived from clear logical thinking, from the intellect (i.e., from "reason").

38 The Wax Example Wax has one set of properties when cold
But all its properties change when heated Yet we still think it’s the same wax. Why? It can’t be the senses that tells us this - they give conflicting reports Can’t be imagination either - wax can change more ways than we can imagine So it must be pure mental scrutiny that reveals the true nature of the wax Hence Rationalism should be adopted over Empiricism

39 Perception In fact all perception is really a case of mental judgement
We say we see a man crossing the square Yet all we see are a hat and cloak which could conceal an automaton Our judgements go beyond what we strictly have sense experience for

40 Meditation 3 Rebuilding knowledge
René Descartes Meditation 3 Rebuilding knowledge

41 Rebuilding Knowledge Descartes’ strategy in rebuilding knowledge rests on 2 central claims: The clear and distinct rule The existence of a benevolent God

42 The Clear and Distinct Rule
What is it that convinces us of the truth of the Cogito? It is a “clear and distinct” perception A psychological state which gives rise to irresistible certainty Hence anything else which is clear and distinct must also be certain This rule can now be used to rebuild knowledge by identifying other truths God’s existence, for example, can be known clearly and distinctly

43 The Trademark Argument
This argument in Meditation 3 helps support the clear and distinct rule We have an idea of God in our mind This idea must have a cause There must be as much reality in the cause as in its effect The cause of the idea is God The idea is like a trademark left in our minds by God The idea of God includes the notion that he is benevolent Hence God is no deceiver Hence whatever we perceive distinctly must be true since a benevolent God wouldn’t allow this level of deception

44 Meditation 6 Resolution of Earlier Doubts
René Descartes Meditation 6 Resolution of Earlier Doubts

45 Naïve Realism The simplistic view that unreflective people have
External objects present themselves to the senses unbidden They are more distinct than those presented by memory or imagination They can’t come from within so must come from without It seems that the sense comes first and the intellect later So nothing is present to the mind that was not first present to the senses

46 Rejection of Naïve Realism
Descartes refers to arguments from Meditation 1 Objects at a distance Phantom limbs Demonstrate the fact that senses don’t always report the truth Dreaming argument I don’t believe the objects in dreams are located outside of me so why make this assumption when awake? But must we resort to scepticism?

47 Rejection of Scepticism
Although we shouldn’t heedlessly accept sense reports, neither should we heedlessly reject them We have a passive faculty for receiving ideas of objects but there must be an external cause to the ideas we receive These causes can only be: External objects God The demon God is not a deceiver so wouldn’t allow us to think that these ideas were caused by external objects when they weren’t

48 Sense Experience There is an outside world
                                                                   There is an outside world However it may not exist in the way it is presented by my senses Everything I am taught by nature contains some truth God equips us with a number of faculties: Reason The Senses Memory It is impossible that there could be any falsity in my opinions which couldn’t be corrected by some faculty supplied by God

49 How is Error Possible? Some things which my senses appear to be telling me are in fact a misjudgement of reason “Grass is green” Grass stimulates sensations of green in us “The tower is small” The tower simply appears small and my memory and other senses can confirm its true size “My amputated foot causes pain” Feelings of pain from a distant body part could equally be caused by stimulating parts in between With the judicial use of clear reasoning we can correct the errors of the senses

50 The Dream Argument Dreams have no consistency between one dream and the next. Life picks up from where it left off but dreams do not The laws of nature are broken in dreams People can fly or talk to dead people By the application of reason we can distinguish the two states when we are awake

51 The Demon Hypothesis If there were a demon, a benevolent God would not allow him to interfere with our perceptions The hypothetical possibility of the demon is therefore no longer a threat

52 Section 2 Option 2 David Hume

53 Enquiry Concerning Human Understanding
David Hume Enquiry Concerning Human Understanding

54 Background Empiricist Philosopher and Historian
A pivotal figure of the Scottish Enlightenment along with Adam Smith ( ) and Thomas Reid ( ) Key Works: A Treatise of Human Nature (1740) An Enquiry Concerning Human Understanding (1748) Dialogues Concerning Natural Religion (1779)

55 Influences Heavily influenced by John Locke ( ), Sir Isaac Newton (1642 – 1727) and Bishop George Berkeley ( ). Hume gets his notions of Empiricism, Representative Realism, and Scientific Method from them.

56 Hume’s Enquiry Inspired by the empirical successes of Isaac Newton wants to do the same for the human mind. He is undertaking a psychological study of man. Trying to uncover the fundamental principles of human reasoning. His method is one of empirical observation. Usually this involves introspection on his own thoughts and feelings.

57 Impressions and Ideas Idea of apple Impression of apple
The Outside World?

58 Supporting Arguments It is impossible to have an idea without first having had a prior impression Hume challenges us to find counter examples Even God is just a complex idea Blind men can’t imagine colours Laplanders can’t imagine the taste of wine Selfish people can’t imagine generosity Some animals have additional senses hence can access additional ideas

59 Simple and Complex Ideas
Impressions Our imagination seems unlimited in its powers However all complex ideas must be based on on simple ideas we have previously copied from an impression Golden Mountain Virtuous Horse God We do this by taking simple ideas and: Augmenting Diminishing Transposing Compounding This supports the empiricist doctrine that “all ideas are ultimately based on sense experience”.

60 Critical Comment Are all impressions more vivid than their ideas?
Faint impressions when drunk; morning after embarrassment Are all ideas more faint than their impressions? Nightmares or traumatic memories Is Hume’s account of perception too simplistic? Cocktail conversations Do all ideas have a prior impression? Ultraviolet; Infrared; gravity Can you ever conceive of simple ideas on their own without thinking of other ideas? E.g. Stripes Hume provides no ‘grammar’ to tell us how to link these ideas up. watch + pocket; zebra + crossing. Can we ever compare an impression with an idea in practice? (Barrier of Ideas) Can we ever compare impressions with the outside world? (Barrier of Impressions)

61 The Missing Shade of Blue
Hume’s own counter example! Imagine You had seen every shade of blue but one Then all shades of blue were arranged on a scale from darkest to lightest Hume asks if we could imagine the missing shade without a prior impression Hume surprisingly says yes but “…it’s so singular and obscure an example it should not alter our general maxim…”

62 Comments on the Missing Shade of Blue
The example is not “singular and obscure”. Missing shade of red; missing note on a scale; missing type of architecture. If not based on impressions the idea must be innate! Threatens to undermine the whole of Empiricism! The example is not insuperable. Hume could say that the missing shade is a complex idea based on simpler ideas. But doesn’t see the solution because he thinks colours must be simple ideas. Demonstrates Hume’s rather cavalier attitude.

63 The Association of Ideas
Why does the thought of one idea lead on to the thought of another? Ideas don’t come randomly they follow an order or pattern and are always related There are 3 principles of the association of ideas: Resemblance Contiguity (In time or space) Cause and Effect So every idea is always related to the next for one of these three reasons

64 Comments and Criticisms
What is the difference between contiguity and cause and effect in Hume’s analysis? Is there really no such thing as a truly random chain of thought? What about people with “Butterfly Brains”? What about people with dementia or Tourettes’? Is the subconscious mind available to us? (Freud) Seems incapable of proof or disproof. Hume says that even if we can’t see the connection in people’s thought it will be apparent to them. What if we ourselves are not even aware of the connection?

65 Hume’s Fork

66 Comments on Hume’s Fork
Hume confuses An epistemological distinction with a semantic distinction A Priori  Analytic A Posteriori  Synthetic Kant claimed that there were synthetic a priori beliefs which tell us about the world but aren’t derived from experience E.g. Every event has a cause. Hume’s fork itself falls foul of the distinction. Is it a matter of fact or a relation of ideas? Hume can’t just say we should disregard all exceptions as nonsense. If he is right exceptions shouldn’t even occur. If they occur at all then his distinction is nonsense

67 Matters of Fact Many knowledge claims concern unobserved matters of fact. Statements about the future (Physics) Statements about the past (History) Statements about far away places (Geography) Even day to day knowledge claims The basis of all our reasoning concerning matters of fact is “cause and effect” But where does our idea of cause and effect come from? An analysis of causes reveal that they have three features: Priority Contiguity Necessity

68 Causation We all have an idea of necessary connection but where does this idea come from? Is it a ‘matter of fact’ or is it a ‘relation of ideas’? Is it acquired by experience a posteriori? No. We have no impression of the ‘necessity’ or ‘power’ transferring between causes and their effects. Is it acquired a priori by reason? No. It’s not true by definition that apples must fall to the ground. Causes don’t resemble effects so we can’t know a priori what the effects of any cause will be.

69 The Origin of our Belief in Causation
Hume provides a psychological justification for our belief in necessary connections Our belief in causes connection is based on ‘custom and habit’ We don’t observe necessary connections, we only actually observe ‘constant conjunctions’. But once we see them often enough we develop an expectation that the future will resemble the past. But this belief is actually irrational. It’s just a fact about human psychology that our brains work this way. It’s basis is simply “custom and habit”. The only reasoning here is the “reason of animals”.


71 Comments Does Hume’s analysis of causation undermine the whole of science? Does Hume’s analysis of causation undermine his whole project? Is Hume claiming that there is no difference between causation and correlation? E.g. Tiredness and the 10 O’Clock News Is temporal priority the only way to distinguish causes from their effects? What about contemporaneous causes? Is Hume’s psychological account a sufficiently complex psychology? E.g. Compulsive gamblers; Alcoholics; abusive partners? Do we need constant conjunction to infer causal connections? E.g. food poisoning or electrocution How significant is contiguity in leading us to infer causal connections?

72 Hume’s Scepticism After rigorously applying his “fork”, Hume admits that his position is in many respects a sceptical one The Outside World: Impressions come “unbidden into the mind…we know not from where”. There may be no world out there. God: Is neither true by definition nor observed. The self: We have no constant impression of a unified self. We are just a bundle of impressions. Moral Values: These aren’t revealed by reason or experience. Just a fact of psychology that we approve of some acts and disapprove of others.

73 Comments on Hume’s Scepticism
A surprising outcome for an empiricist philosopher. “Hume developed empiricism to its logical conclusion and more or less destroyed it by doing so” Richard Osborne Leaves us knowing not very much for certain. Descends into Solipsism Must we accept Representative Realism? Must we accept foundationalism?

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